Aromatizing edible oils

ABSTRACT

Edible oils are aromatized by adding the oil to a cryogenic fluid to form a slurry, adding an aroma-bearing frost to the slurry, and allowing the mixture to equilibriate at temperatures above the boiling point of the cryogenic fluid for a period of time sufficient to evaporate the cryogenic fluid leaving a residue of aroma-enhanced oil.

United States Patent [191 Patel Jan. 1,1974

[52] US. Cl 426/221, 426/386, 426/417 [5 l] Int. Cl. A23f 1/04 [58]Field of Search 99/65, 71, 140 A [56] References Cited UNITED STATESPATENTS 12/1942 Johnston t. 99/71 lO/l968 Klein et al. 99/7] 2,947,6348/1960 Feldman et al. 99/71 2,680,687 6/1954 Lemonnicr i 99/7l 3,021,2182/l962 Clinton et al. 99/7l Primary Examiner-Frank W. Lutter AssistantExaminer-William L. Mentlik Attorney-Richard C. Witte et al.

[57] ABSTRACT Edible oils are aromatized by adding the oil to acryogenic fluid to form a slurry, adding an aroma-bearing frost to theslurry, and allowing the mixture to equilibriate at temperatures abovethe boiling point of the cryogenic fluid for a period of time sufficientto evaporate the cryogenic fluid leaving a residue of aromaenhanced oil.

11 Claims, No Drawings AROMATIZING EDIBLE OILS BACKGROUND OF THEINVENTION An age-old problem in the instant coffee art has been, andstill is, to prepare instant coffees having the same aroma as roast andground coffee itself. Many methods have been utilized in attempting toapproach this desired end result. For example, aroma materials have beensteam stripped from roast and ground coffee and added back to instantcoffee after complete processing; and coffee oil has been expelled fromcoffee beans' and added back to final instant coffee product as anaroma-enhancing material. Other techniques which have commonly beenemployed include dry distillation of coffee beans to obtain aromamaterials, utilization of complicated extraction processes in order toobtain coffee aroma materials, and the like. One method disclosed in theprior art is to obtain an aroma frost by low temperature condensationmethods. Aroma frost is a low temperature condensate of volatiles whichescape during coffee processing, for example, during roasting, grinding,steam distillation, extracting where it is employed, and drydistillation and the like. These volatile constituents are oftenobtained by low temperature condensation of escaping gaseous material,for example at liquid nitrogen temperatures, by passing the escaping gasthrough a liquid nitrogen trap to yield a condensate which is referredtoherein as an aroma frost.

' The aroma frost may be grinder gas frost, roaster gas frost, a drydistillation frost, a stream distillation frost, and the like. Forexamples of patents relating to methods of providing aroma frost, seefor example, Lemonnier, U.S. Pat. No. 2,680,687, issued June 8, 1954; U.S. Pat. No. 3,021,218, Clinton et al., issued Feb. 13, I962; Kline, U.S. Pat. No. 3,406,074; Mook et al., U.S. Pat. No. 3,035,922, issued May.22, 1962; and Kline et al., US. Pat. No. 3,535,118, issued Oct. 20,1970.

However, once obtained, to be of value aroma frost must then beincorporated in a relatively stable manner into the coffee product whoseroast and ground coffee aroma is desired to be increased. Typically,this coffee product is an instant coffee because instant coffees arenotably deficient in characteristic roast and ground coffee aroma.Additionally, the aroma frost itself must be incorporated into a stablecarrier in order to have any significant amount of retained aroma value.The most common carrier is coffee oil. For further details relating tomethods of incorporating aroma-enriched coffee oil into coffee products,see the copending application of Lubsen et al. entitled Aroma-enrichedCoffee Products and Process," filed Oct. 15, I971, Ser. No. 189,746.

Of course, a first problem that must be confronted in aroma enrichingcoffee products is incorporation of aroma frost into a stable oil, suchas cofiee oil, in a manner which most efficiently imparts the highestpossible amount of aroma to the coffee oil. The process of thisinvention relates to a technique of incorporating aroma frost intoedible oils in such a manner that the amount of aroma-enrichingcomponents incorporated into the oil is at the highest possible levelcommensurate with practical processing techniques. While the primaryutility of the process of this invention is in the field ofincorporating coffee aroma frost into coffee oil, it should beunderstood that this technique has broader applicability and could, forexample, be utilized in the preparation of aroma-enhanced products suchas instant beverage drinks prepared from all common fruits andvegetables. Accordingly, while the majority of the description ispresented herein with regard to the method of incorporating aroma intocoffee oil, such a presentation is presented for convenience ofdescription only and the invention is not to be limited thereby.

It is an object of this invention to provide a process of aromatizingedible oils with aroma frost in a manner which allows incorporation intothe oil of a high level of aroma frost thereby producing anaroma-enriched oil capable of enhancing to a high degree the aroma ofany desired product to which the aromatized oil is added. I

The method of accomplishing this and other objects will become apparentfrom the following description of the invention.

SUMMARY OF THE INVENTION This invention relates to a process ofaromatizing edible oils which has been found to impart to the oil thedesired aroma components of an aroma frost at a high intensity level.Therefore the resulting aroma-enriched oil can be utilized as aneffective aroma-enhancing material when added back to products such asinstant coffees. In one particular embodiment, the process comprisespouring the edible oil into a cryogenic fluid to form a slurry, addingaroma frost to the slurry, preferably mixing the slurry, and allowingthe mixture to equilibrate at temperatures above the boiling point ofthe cryogenic fluid for a period of time sufficient to evaporate thecryogenic fluid leaving behind a residue of aroma-enriched oil.

DETAILED DESCRIPTION OF THE INVENTION The edible oil which is to beutilized in the process of this invention can be obtained from a varietyof sources. And, of course, the precise edible oil utilized depends uponthe product whose aroma is to be enhanced. The edible oil which can beof either animal or vegetable origin, can include common triglycerideoils such as soybean oil, rapeseed oil, corn oil, marine oils, animaloils, and oils extracted from fruits, berries and vegetables. Of course,where the product whose aroma is to be enhanced is coffee, the mostconveniently obtained and used oil is coffee oil.

Cofiee oil is obtained by utilizing extraction methods well known in theart to obtain the oil from roast and ground coffee. Generally, two basicextraction methods are employed. The first comprises a liquid extractionprocess wherein extractives such as ether are utilized to remove coffeeoil from roast and ground coffee. In this process the extractive aftercontact with the roast and ground cofiee is removed to yield a residueof coffee oil. However, the far more common process comprises expressingcoffee oil from roast and ground coffee beans by subjecting the beans toextreme pressure conditions. The product of this process is oftenreferred to as expressed coffee oil, and since expressed cofiee oil hasthe advantage of not requiring the addition of foreign materials toobtain the coffee oil, expressed coffee oil is most often utilized inpreparation of instant coffees.

According to the process of this invention the edible oil whose aroma isto be enhanced by incorporating therein an aroma frost is first pouredinto a cryogenic fluid to form an oil-cryogenic fluid slurry. As usedherein, the term cryogenic fluid is used in its traditional sense asdefined in the Condensed Chemical Dictionary, 6th edition, at page 316,wherein cryogenics is referred to as a field of science dealing with thebehavior of matter at very low temperatures and with low temperaturetechniques, for example, the use of liquefied gases such as oxygen,nitrogen, and hyrogen at temperatures as low as 260 C. As used hereinthe the terms poured" and added are used interchangeably to define anymanner of incorporating into the cryogenic fluid the edible oil andaroma frost.

When the edible oil, which is preferably at room temperature, is pouredinto a cryogenic fluid, because of the wide temperature differentialseveral important things occur. Because of the extremely low temperature of the cryogenic fluid the edible oil virtually instantly freezesand fractures into very small particles, providing a frozen finelydivided oil-cryogenic fluid slurry. While this rapid freezing and andsimultaneous fracturing is occurring, the cryogenic fluid issimultaneously evaporating which results in a very highly porousstructure within the divided frozen oil particles. The resulting finelydivided frozen oil particles with a highly porous structure areespecially suitable for incorporation of aroma because the fine state ofparticle subdivision allows for maximum contact between an aroma frostand the frozen oil, and the very porous nature of the divided particlesallows for easy incorporation of aroma frost into the oil itself.

The ratio of oil to cryogenic fluid in this first step is not criticaland optimization of that ratio for any particular oil can easily beaccomplished. For coffee oil the ratio of coffee oil to cryogenic fluidshould be within the range of from 1:10 to 1:1, preferably within therange of from [:2 to l:5. Experimental results have shown that at leastfor coffee oil it is preferred that the amount of cryogenic fluid be atleast twice as great as the amount of coffee oil in order to insure thatthe above-described phenomenon of simultaneously freezing and fracturingto provide a highly porous subdivided frozen oil will occur. There is nocriticality with regard to the maximum amount of cryogenic fluidutilized and the upper limits given herein are merely practical limits.

The cryogenic fluid utilized in this first step can be any of theconventionally known cryogenic fluids such as liquid nitrogen, liquidair, liquid oxygen, liquid hydrogen, liquid helium, and the like.However, the most easily obtained and perhaps one of the most inertcryogenic fluids is liquid nitrogen, and it is therefore preferred fromthe standpoint of availability as well as safety during use. Of course,other cryogenic fluids, as should be apparent to those skilled in theart, can also be employed with satisfactory performance results.

In the next step of the process of this invention, aroma frost is addedto the frozen oil-cryogenic fluid slurry to provide an aromafrost-slurry mixture. No criticality exists with regard to the precisearoma frost employed and it can be obtained from those sourcespreviously described. For example, if the aroma frost is to be a coffeearoma frost it can be an aroma frost collected and condensed at very lowtemperatures from various points in the processing of coffee to produceeither instant coffee products or roast and ground coffee products. Forexample with regard to roast and ground coffee frost, grinder gas can becollected as a grinder gas frost, and where the coffee is a flakedcoffee, gases escaping during compression to form flakes can becollected to form a flaking gas frost. With regard to instant coffeeprocessing, frost can be obtained during dry distillation of roast andground coffee beans, steam distillation of roast and ground coffeebeans, and other similar processing steps. For details with regard to animportant improvement in the manner of collecting aroma frost, see thecopending application of Patel et al., Ser. No. 188,924, filed Oct. 13,1971, entitled Improved Aroma Condensation Process. For other methods ofcollecting aroma frost see the previously cited patents, in particularthe Lemonnier, Mook, and Kline patents, as well as the copendingapplication of Strobel, Ser. No. l58,590, filed June 30, 1971 now U.S.Pat. No. 3,717,472, entitled Separating Aroma and Flavor Substrates lntoAroma-and Flavor-Bearing Concentrates.

it is preferred, although not essential, that additional mixing occurafter adding the aroma frost to the frozen subdivided porousoil-cryogenic fluid slurry. In this manner most intimate contact isinsured. Preferably, where mixing or agitation is employed during theaddition of aroma frost, the mixing is stopped and the combined mixtureof aroma frost, frozen finely subdivided porous oil and cryogenic fluidslurry is allowed to stand under non-agitating conditions. When thisoccurs the solid material will settle to the bottom as a heterogeneousdeposit, which of course allows further maximum contact on a solidparticle-to-solid particle basis.

In the next step of the process the maximum is allowed to equilibrate attemperatures above the boiling point of the cryogenic fluid at least fora period of time sufficient to evaporate the cryogenic fluid and leavehehind a residue of aroma-enhanced oil. No criticality is associatedwith the precise temperature employed here as long as the temperature isabove the boiling point of cryogenic fluid. temperatures up to ambientconditions can be employed. However, for liquid nitrogen, temperatureswithin the range of from above the subliming point of C0 (-1 10 F) up to0 F are preferred. During this step all undesired gases which arepresent are removed, such as for example carbon dioxide, carbonmonoxide, and nitrogen. After the cryogenic fluid has completelyevaporated, the coffee oil-aroma frost mixture has warmed sufficientlysuch that it is again liquid and is a significantly aroma-enhancedproduct suitable for addition to products whose aroma is desired to beincreased, such as, for example, instant coffees.

While not essential in the broadest aspect of this invention but highlypreferred, a further improvement in aroma enrichment has been notedwhere the aroma frost-edible oil mixture is allowed to equilibrate attemperatures not in excess of 0 F for at least a period of 8 hours, andfor longer periods if desired. During this equilibration period more ofthe desirable aroma constituents are absorbed into the oil whileadditional undesirable constituents are apparently volatilized togaseous form and lost. After completion of this aroma incorporationtechnique the aroma-enriched edible oil is then suitable for ultimateuse in enhancing the aroma of consumer products such as, for exampleinstant coffee, instant orange juice drinks, and other instant beveragedrinks.

it should be understood that while the above description has been givenin the context of first pouring edible oil into the cryogenic fluid andthereafter adding aroma frost to the cryogenic fluid-frozen oil slurrythat this order of events has been presented merely for convenience ofdescription, and should not be taken as limiting. If desired the aromafrost can be first added to the cryogenic fluid and the edible oil addedthereafter or the edible oil and the frost can be added simultaneously.

The following Examples are intended to illustrate but not limit theprocess of this invention as described.

EXAMPLE 1 An orange aroma frost is obtained in the manner described incopending application of Patel et al., Ser. No. 74.074, filed Sept. 21,1970, and now abandoned, entitled Cryogenic Aromatization of InstantCoffee. In particular, 2 pounds of sliced oranges were placed in avessel which was in close communication with a finger trap held at -320F by a bath of liquid nitrogen. The first portion of the vesselcontaining the sliced oranges was maintained at 70 F. Aroma materialsescaping from the sliced fresh oranges traveled across the communicatingline and condensed in the cold finger trap. Condensation continued until0.5 grams of orange aroma frost was obtained.

0.5 grams of orange oil, which is an edible oil, was poured into, liquidnitrogen, a cryogenic fluid, to form an oil cryogenic fluid slurry. Theratio of orange oil to cryogenic fluid was 1:40. When the orange oil waspoured into the liquid nitrogen it virtually instantly froze andfractured into very small particles, providing a frozen finely dividedoil cryogenic fluid slurry. Simultaneously with this phenomenon,cryogenic fluid was evaporating from the slurry which in turn caused ahigh degree of porosity in the frozen edible oil particles. 0.5 grams ofaroma frost was added to the frozen finely divided edible oil liquidnitrogen slurry, mixed, and allowed to equilibrate at F for 24 hours.

Thereafter a panel of experts compared the aroma body and intensity ofaroma-enhanced orange oil with orange oil which had not been treated inaccord with the process of this invention, and found the orange oilprepared in accord with the process of this invention to be more sweet,have more body, and a distinctly more fresh orange-like aroma.

EXAMPLE 2 Coffee aroma which normally escapes from roast and groundcoffee during grinding, i.e., grinder gas, was swept away from grindersand condensed in a trap held at liquid nitrogen temperatures to producea grinder gas frost. Aroma frost was collected until a S-pound batchresulted.

5 pounds of coffee oil was poured into 12 pounds of liquid nitrogen at-320 F. Coffee oil which was poured into the liquid nitrogen was at roomtemperature. Virtually instantaneously upon pouring into the liquidnitrogen the coffee oil froze and fractured into finely dividedparticles. The frozen subdivided coffee oil particles upon closeexamination revealed a high degree of porosity, indicating thatevaporating liquid nitrogen induced the formation of very porousparticles ideally suited for aroma frost incorporation. The abovereferred to 5 pounds of grinder gas frost was placed in the coffee oilliquid nitrogen slurry and mixed for about 10 minutes. The mixture wasallowed to stand for approximately 10 to 15 minutes until the majorityof the liquid nitrogen had evaporated. Thereafter the remaining aromafrost frozen/coffee oil mixture was allowed to equilibrate at 0 F forabout 24 hours. During this equilibration period the oil/aroma frostmixture warms up to 0 F and undesirable gases escape therefrom. It isalso believed that aroma diffuses into the coffee oil during theequilibration period.

The oil is allowed to warm to room temperature slowly. Thereafter apanel smells the aroma-enriched oil and compares that smell tounaromatized oil and unanimously noted that the aroma-enhanced oil wassignificantly more coffee-like in aroma.

Equivalent results are obtained in this example when the grinder gasaroma frost is added to the liquid nitrogen first and the edible oil isadded thereafter, and when the edible oil and the aroma frost are addedto the liquid nitrogen simultaneously.

What is claimed is:

l. A process of aromatizing edible oils, comprising adding said oil to acryogenic fluid to form an oilcryogenic fluid slurry, adding aroma frostto said slurry to provide an aroma frost-slurry mixture, allowing saidmixture to equilibrate at temperatures above the boiling point of thecryogenic fluid for a period of time sufficient to evaporate thecryogenic fluid leaving a residue of aroma-enhanced oil.

2. The process of claim 1 wherein the edible oil is a triglyceride oil.

3. The process of claim 1 wherein the edible oil is coffee oil.

4. The process of claim 1 wherein the aroma frost is a coffee aromafrost.

5. The process of claim 41 wherein the aroma frost is selected from thegroup consisting of roaster gas frost, grinder gas frost, drydistillation frost, a steam distillation frost, and a flaking gas frost.

6. The process of claim 5 wherein the cryogenic fluid is liquidnitrogen.

7. The process of claim 6 wherein the ratio of coffee oil to liquidnitrogen is from 1:10 to 1:1.

8. The process of claim 7 wherein the equilibration temperature iswithin the range of from just above the subliming point of carbondioxide up to 0F.

9. The process of claim 8 wherein the equilibration time is at least 8hours. I

10. The product of the process of claim ll.

11. A process of aromatizing edible oils comprising adding aroma frostto a cryogenic fluid, adding an edible'oil to said cryogenic fluid andallowing said mixture to equilibrate at temperatures above the boilingpoint of the cryogenic fluid for a period of time sufficient toevaporate the cryogenic fluid leaving a residue of aroma-enhanced oil.

0 w a: a

"H050 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.163 Dated January 1/ 1974 Inventor(s) Jaya ntilal M. Patel It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby c'iorrected as shown below:

Column 1, line 2-9 "stream" should be steam .1

Column 3, line'5 "hyrogen" should be hydrogen Column 4, line 28"maximum" should be mixture Column 4, line 3 5 temperatures" should becapitalized.

Signed and sealed this L th day of June 19711,.

(SEAL) Atteat:

EDWARD M.FLETCHER,JR. c. MARSHALL 1mm Atteating Officer Commissioner ofPatents

2. The process of claim 1 wherein the edible oil is a triglyceride oil.3. The process of claim 1 wherein the edible oil is coffee oil.
 4. Theprocess of claim 1 wherEin the aroma frost is a coffee aroma frost. 5.The process of claim 4 wherein the aroma frost is selected from thegroup consisting of roaster gas frost, grinder gas frost, drydistillation frost, a steam distillation frost, and a flaking gas frost.6. The process of claim 5 wherein the cryogenic fluid is liquidnitrogen.
 7. The process of claim 6 wherein the ratio of coffee oil toliquid nitrogen is from 1:10 to 1:1.
 8. The process of claim 7 whereinthe equilibration temperature is within the range of from just above thesubliming point of carbon dioxide up to 0*F.
 9. The process of claim 8wherein the equilibration time is at least 8 hours.
 10. The product ofthe process of claim
 1. 11. A process of aromatizing edible oilscomprising adding aroma frost to a cryogenic fluid, adding an edible oilto said cryogenic fluid and allowing said mixture to equilibrate attemperatures above the boiling point of the cryogenic fluid for a periodof time sufficient to evaporate the cryogenic fluid leaving a residue ofaroma-enhanced oil.